Based on the discussion found at foundation issue #1358 https://github.com/zurb/foundation/issues/1358#issuecomment-28546603

gistfile1.js

$(window).load(function() {
  $("[data-match-height]").each(function() {
    var parentRow = $(this),
      childrenCols = $("> [data-height-watch]", this),
      childHeights = childrenCols.map(function(){ return $(this).outerHeight(); }).get(),
      tallestChild = Math.max.apply(Math, childHeights);
    childrenCols.css('min-height', tallestChild);
  });
});

gistfile2.css

[data-height-watch] {
  border-left: 1px solid gray;
}
[data-match-height] > [data-height-watch][data-height-watch-novrule] {
  border-left: 0 none;
}

@media only screen and (max-width:1023px) {
  [data-height-watch] {
    min-height: 1px !important;
    border-left: 0 none !important;
  }
}

gistfile3.html

<div class="row" data-match-height>
  <div class="medium-12 large-9 large-push-3 columns" data-height-watch>
    Main column on the right
  </div>
  <div class="large-3 large-pull-9 columns" data-height-watch data-height-watch-novrule>
    Sidebar column on the left
  </div>
</div>